diff --git a/src/hb-bit-set-invertible.hh b/src/hb-bit-set-invertible.hh
index 512107ffd..27fb0732e 100644
--- a/src/hb-bit-set-invertible.hh
+++ b/src/hb-bit-set-invertible.hh
@@ -80,7 +80,7 @@ struct hb_bit_set_invertible_t
     next (&v);
     return v == INVALID;
   }
-  uint32_t hash () const { return s.hash () ^ inverted; }
+  uint32_t hash () const { return s.hash () ^ (uint32_t) inverted; }
 
   hb_codepoint_t get_min () const
   {